Traveling control method and device of self-driving mine car and readable storage medium

Abstract

The invention provides a driving control method and device for an automatic driving mine car and a readable storage medium, and the method comprises the steps: obtaining a speed curve in the global path planning of the mine car, and carrying out the smoothing processing, so as to obtain a first speed curve; determining whether the mine car has a target behavior; determining a first target speed according to the first speed curve and the current GPS speed of the mine car under the condition that the mine car does not have the target behavior, and controlling the mine car to run according to the first target speed; otherwise, generating a plurality of second speed curves according to the current position information, the speed information, the acceleration information and the parameter information of the end point, and screening out a third speed curve; generating a second target speed according to the third speed curve and the current GPS speed of the mine car; controlling the tramcar to run according to the second target speed. According to the method provided by the invention, the comfort and safety of the self-driving mine car in surface mine operation can be remarkably improved, and potential safety hazards such as emergency stop failure caused by improper speed planning are avoided.

Description

Technical Field

[0001] The present invention relates to the field of unmanned driving technology, and in particular to a driving control method, device and readable storage medium for an autonomous driving mining vehicle. Background Art

[0002] The operating environment of open-pit mines is complex, such as muddy and bumpy roads, steep slopes, changeable climate, and prone to wind, sand, rain, snow and other weather conditions. Different working conditions require vehicles to travel at different speeds, ensuring both transportation efficiency and safety, which puts higher demands on the speed planning of autonomous vehicles. Existing speed planning schemes often face problems such as insufficient smoothness, large amount of calculation, and great impact on vehicle comfort. In addition, in specific scenarios (such as emergency parking and following vehicles), decisions are prone to frequent jumps, resulting in large speed fluctuations and increased safety risks.

[0003] Therefore, how to propose a driving control method for an autonomous driving mine car that can comprehensively consider multiple factors, achieve smooth speed planning, and ensure driving safety and comfort has become a problem that needs to be solved urgently. Summary of the invention

[0004] The present invention aims to at least solve the problem in the prior art or related art that the self-driving mine car cannot achieve speed smoothness, resulting in low comfort and safety of the self-driving mine car.

[0005] Therefore, the first object of the present invention is to provide a driving control method for an automatic driving mine car.

[0006] A second object of the present invention is to provide a driving control device for an automatic driving mine car.

[0007] The third object of the present invention is to provide a driving control device for an automatic driving mine car.

[0008] A fourth object of the present invention is to provide a readable storage medium.

[0009] The technical solution of the first aspect of the present invention provides a driving control method for an automatic driving mine car, including: obtaining a speed curve in the global path planning of the mine car; smoothing the speed curve to obtain a first speed curve; determining whether the mine car has a target behavior; when it is determined that the mine car has not had the target behavior, determining a first target speed according to the first speed curve and the current GPS speed of the mine car, and controlling the mine car to travel according to the first target speed; when it is determined that the mine car has had the target behavior, obtaining the current position information, speed information, acceleration information and parameter information of the end point of the mine car; generating multiple second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point; screening the multiple second speed curves to obtain a third speed curve; determining a second target speed according to the third speed curve and the current GPS (Global Positioning System) speed of the mine car; and controlling the mine car to travel according to the second target speed.

[0010] According to the driving control method of the automatic driving mine car provided by the present invention, by smoothing the speed curve in the global path planning of the mine car, the sudden change of speed can be reduced, thereby improving the comfort and stability of the vehicle driving. The mine car may have target behaviors during driving, such as deceleration, acceleration and lane change, so the original planned speed is no longer applicable. At this time, it is necessary to generate multiple second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point of the mine car, and then select the optimal second speed curve from the multiple second speed curves, recorded as the third speed curve, and finally determine the second target speed according to the third speed curve and the current GPS speed of the mine car, so that the mine car travels at the second target speed. It can be understood that the second speed curve is generated according to the current position information, speed information, acceleration information and parameter information of the end point of the mine car, which can ensure that the speed curve remains continuous and smooth during the change process. The first target speed is determined according to the first speed curve and the current GPS speed of the mine car, or the second target speed is determined according to the third speed curve and the current GPS speed of the mine car, which is to merge the planned speed curve with the actual vehicle speed to ensure that the vehicle is more stable when performing actions and that the vehicle does not start or stop too suddenly. Therefore, this application can significantly improve the comfort and safety of self-driving mine cars in open-pit mine operations, and effectively avoid safety hazards such as emergency stop failures caused by improper speed planning.

[0011] In addition, the driving control method of the autonomous driving mine car provided in this application may also have the following additional technical features:

[0012] In some embodiments, optionally, the step of smoothing the speed curve to obtain the first speed curve includes: smoothing the speed curve using a conjugate gradient method to obtain the first speed curve.

[0013] In this embodiment, the conjugate gradient method can be used to smooth the speed curve to reduce the speed mutation between adjacent planning frames and improve driving smoothness. The conjugate gradient method has the characteristics of high efficiency and fast convergence speed, and can quickly perform preliminary smooth optimization on the received speed information.

[0014] In some embodiments, the target behaviors may optionally include: cruising, decelerating to stop, accelerating to overtake, starting after stopping, and changing lanes.

[0015] In this embodiment, the target behaviors include: cruising, decelerating to stop, accelerating to overtake, starting after stopping, and changing lanes. Of course, it is not limited to these, and it can also be behaviors such as turning.

[0016] In some embodiments, optionally, the step of generating multiple second speed curves based on current position information, speed information, acceleration information and parameter information of the endpoint includes: generating multiple second speed curves using quintic polynomial interpolation based on the current position information, speed information, acceleration information and parameter information of the endpoint.

[0017] In this embodiment, the current position information, speed information, acceleration information and parameter information of the end point of the mine car can be integrated, and a plurality of second speed curves can be generated by using quintic polynomial interpolation to ensure the authenticity and continuity of the acceleration.

[0018] In some embodiments, optionally, the step of screening multiple second speed curves to obtain a third speed curve includes: screening multiple second speed curves according to preset constraints and cost values ​​to obtain a third speed curve; wherein the preset constraints include centripetal acceleration, longitudinal displacement of the mine car, coordinate point information, monotonicity of speed in acceleration and deceleration stages, maximum speed and maximum acceleration limits.

[0019] In this embodiment, multiple second speed curves can be screened according to preset constraints and cost values ​​to obtain a third speed curve. For example, the second speed curve satisfies the centripetal acceleration constraint, while ensuring that the longitudinal displacement is monotonically increasing, the planned end point coordinates do not exceed the target point coordinates, the speed is monotonous in the acceleration and deceleration stages, and the maximum speed and maximum acceleration limits.

[0020] In some embodiments, optionally, the step of determining the second target speed according to the third speed curve and the current GPS speed of the mine car includes: determining the second target speed using a first-order Bezier curve according to the third speed curve and the current GPS speed of the mine car.

[0021] In this embodiment, the first-order Bezier curve can be used to smooth the output speed according to the third speed curve and the current GPS speed of the mining vehicle to determine the target speed and avoid starting or braking too quickly.

[0022] In some embodiments, optionally, after the step of controlling the travel of the mine car according to the first target speed or the second target speed, the travel control method of the autonomous driving mine car further includes: adjusting the following distance according to the current speed of the mine car, the braking response distance and the slope information.

[0023] In this embodiment, in the following mode, the current speed, brake response distance and slope information can be comprehensively considered to dynamically adjust the following distance, reduce speed fluctuations caused by behavioral decisions, and ensure safety.

[0024] The technical solution of the second aspect of the present invention provides a driving control device for an automatic driving mine car, comprising: an acquisition module for acquiring a speed curve in the global path planning of the mine car; a first processing module for smoothing the speed curve to obtain a first speed curve; a first determination module for determining whether the mine car has a target behavior; a first control module for determining a first target speed according to the first speed curve and the current GPS speed of the mine car when it is determined that the mine car has not had the target behavior, and controlling the mine car to travel according to the first target speed; a second determination module for acquiring the current position information, speed information, acceleration information and parameter information of the end point of the mine car when it is determined that the mine car has had the target behavior; a second processing module for generating multiple second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point; a screening module for screening multiple second speed curves to obtain a third speed curve; a third determination module for determining a second target speed according to the third speed curve and the current GPS speed of the mine car; and a second control module for controlling the mine car to travel according to the second target speed.

[0025] The driving control device of the automatic driving mine car provided by the present invention comprises an acquisition module, a first processing module, a first control module, a first determination module, a second control module, a second determination module, a second processing module, a screening module and a third determination module. The acquisition module can acquire the speed curve in the global path planning of the mine car. The first processing module can smooth the speed curve to obtain the first speed curve. The first determination module can determine whether the mine car has a target behavior. The first control module can determine the first target speed according to the first speed curve and the current GPS speed of the mine car when it is determined that the mine car has not had the target behavior, and control the mine car to travel according to the first target speed. The second determination module can acquire the current position information, speed information, acceleration information and parameter information of the end point of the mine car when it is determined that the mine car has had the target behavior. The second processing module can generate multiple second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point. The screening module can screen multiple second speed curves to obtain a third speed curve. The third determination module can determine the second target speed according to the third speed curve and the current GPS speed of the mine car. The second control module can control the mine car to travel according to the second target speed. The driving control device of the automatic driving mine car provided by the present invention can reduce the sudden change of speed by smoothing the speed curve in the global path planning of the mine car, thereby improving the comfort and stability of the vehicle driving. The second speed curve is generated according to the current position information, speed information, acceleration information and parameter information of the end point of the mine car, which can ensure that the speed curve remains continuous and smooth during the change process. The first target speed is determined according to the first speed curve and the current GPS speed of the mine car, or the second target speed is determined according to the third speed curve and the current GPS speed of the mine car, which is to merge the planned speed curve with the actual vehicle speed to ensure that the vehicle is more stable when performing actions and that the vehicle will not be too sudden when starting or stopping.

[0026] The technical solution of the third aspect of the present invention provides a driving control device for an autonomous mining car, comprising: a memory and a processor, wherein the memory stores a program or instruction, and when the program or instruction is executed by the processor, the steps of the driving control method for an autonomous mining car as in any technical solution of the first aspect are implemented.

[0027] The driving control device of the autonomous mine car provided by the present invention includes a memory and a processor, wherein the memory stores a program or instruction, and when the program or instruction is executed by the processor, the steps of the driving control method of the autonomous mine car in any technical solution of the first aspect are implemented. Since the driving control device of the autonomous mine car can implement the steps of the driving control method of the autonomous mine car in any technical solution of the first aspect. Therefore, the driving control device of the autonomous mine car provided by the present invention also has all the beneficial effects of the driving control method of the autonomous mine car in any technical solution of the first aspect, which will not be repeated here.

[0028] The technical solution of the fourth aspect of the present invention provides a readable storage medium on which a program or instruction is stored. When the program or instruction is executed, the steps of the driving control method of the automatic driving mining car in any technical solution of the first aspect are implemented.

[0029] According to the readable storage medium provided by the present invention, a program or instruction is stored thereon, and when the program or instruction is executed, the steps of the driving control method of the autonomous driving mine car in any technical solution of the first aspect are implemented. Since the readable storage medium can implement the steps of the driving control method of the autonomous driving mine car in any technical solution of the first aspect. Therefore, the readable storage medium provided by the present invention also has all the beneficial effects of the driving control method of the autonomous driving mine car in any technical solution of the first aspect, which will not be repeated here.

[0030] Additional aspects and advantages of the present invention will become apparent from the following description or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is one of the flow charts of a driving control method of an autonomous driving mining vehicle according to an embodiment of the present invention;

[0032] Figure 2 This is a second flow chart of a driving control method of an automatic driving mining vehicle according to an embodiment of the present invention;

[0033] Figure 3 is one of the block diagrams of a driving control device for an autonomous mining vehicle according to an embodiment of the present invention;

[0034] Figure 4 This is the second block diagram of the driving control device of the automatic driving mine car according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] In order to more clearly understand the above-mentioned purpose, features and advantages of the present invention, the present invention is further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0036] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways different from those described herein. Therefore, the protection scope of the present invention is not limited to the specific embodiments disclosed below.

[0037] Refer to the following Figures 1 to 4 The present invention describes a driving control method, device and readable storage medium for an autonomous mining vehicle according to some embodiments of the present invention.

[0038] In one embodiment according to the first aspect of the present application, Figure 1 As shown, a driving control method for an automatic driving mine car is provided, comprising:

[0039] S102, obtaining a speed curve in the global path planning of the mine car.

[0040] S104: Smoothing the speed curve to obtain a first speed curve.

[0041] S106, determining whether the mine car has performed a target behavior.

[0042] S108, when it is determined that the mine car has not performed the target behavior, a first target speed is determined according to the first speed curve and the current GPS speed of the mine car, and the mine car is controlled to travel according to the first target speed.

[0043] S110, when it is determined that the mine car has a target behavior, obtaining the current position information, speed information, acceleration information and parameter information of the end point of the mine car.

[0044] S112, generating a plurality of second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point.

[0045] S114, screening the plurality of second speed curves to obtain a third speed curve.

[0046] S116, determining a second target speed according to the third speed curve and the current GPS speed of the mining car.

[0047] S118, controlling the mine car to travel according to the second target speed.

[0048] According to the driving control method of the automatic driving mine car provided by the present invention, by smoothing the speed curve in the global path planning of the mine car, the sudden change of speed can be reduced, thereby improving the comfort and stability of the vehicle driving. The mine car may have target behaviors during driving, such as deceleration, acceleration and lane change, so the original planned speed is no longer applicable. At this time, it is necessary to generate multiple second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point of the mine car, and then select the optimal second speed curve from the multiple second speed curves, recorded as the third speed curve, and finally determine the second target speed according to the third speed curve and the current GPS speed of the mine car, so that the mine car travels at the second target speed. It can be understood that the second speed curve is generated according to the current position information, speed information, acceleration information and parameter information of the end point of the mine car, which can ensure that the speed curve remains continuous and smooth during the change process. The first target speed is determined according to the first speed curve and the current GPS speed of the mine car, or the second target speed is determined according to the third speed curve and the current GPS speed of the mine car, which is to merge the planned speed curve with the actual vehicle speed to ensure that the vehicle is more stable when performing actions and that the vehicle does not start or stop too suddenly. Therefore, this application can significantly improve the comfort and safety of self-driving mine cars in open-pit mine operations, and effectively avoid safety hazards such as emergency stop failures caused by improper speed planning.

[0049] In some embodiments, optionally, the step of smoothing the speed curve to obtain the first speed curve includes: smoothing the speed curve using a conjugate gradient method to obtain the first speed curve.

[0050] In this embodiment, the conjugate gradient method can be used to smooth the speed curve to reduce the speed mutation between adjacent planning frames and improve driving smoothness. The conjugate gradient method has the characteristics of high efficiency and fast convergence speed, and can quickly perform preliminary smooth optimization on the received speed information.

[0051] In some embodiments, optionally, smoothing the speed curve using the conjugate gradient method includes adjusting the speed value of the current planning frame to reduce the speed mutation between adjacent planning frames.

[0052] In some embodiments, optionally, the following formula may be used to smooth the speed curve:

[0053] V i =V i ˋ-α×(V i ˋ-V i );

[0054] V i =V iˋ-β×[(V i ˋ-V i-1 ˋ)+(V i ˋ-V i+1 ˋ)];

[0055] V i =V i ˋ-β×[(2×V i ˋ-V i-1 ˋ-V i+1 ˋ)];

[0056] Among them, V i ˋ represents the true value of the current element; V i Represents the fitting value of the current element; V i-1 ˋ represents the fitted value of the previous element of the current element; V i+1 ˋ represents the fitting value of the next element after the current element; α represents the fitting weight coefficient between the fitting value and the target value; β represents the smoothing weight coefficient of the difference between the current element and the previous element, and the difference between the current element and the next element.

[0057] In some embodiments, the target behaviors may optionally include: cruising, decelerating to stop, accelerating to overtake, starting after stopping, and changing lanes.

[0058] In this embodiment, the target behaviors include: cruising, decelerating to stop, accelerating to overtake, starting after stopping, and changing lanes. Of course, it is not limited to these, and it can also be behaviors such as turning.

[0059] In some embodiments, optionally, the step of generating multiple second speed curves based on current position information, speed information, acceleration information and parameter information of the endpoint includes: generating multiple second speed curves using quintic polynomial interpolation based on the current position information, speed information, acceleration information and parameter information of the endpoint.

[0060] In this embodiment, the current position information, speed information, acceleration information and parameter information of the end point of the mine car can be integrated, and a plurality of second speed curves can be generated by using quintic polynomial interpolation to ensure the authenticity and continuity of the acceleration.

[0061] In some embodiments, optionally, the quintic polynomial interpolation formula is:

[0062] Yt=a 0 +a 1 ×t+a 2 ×t 2 +a 3 ×t 3 +a 4 ×t 4 +a 5 ×t 5 ;

[0063] Ytˋ=a 1 +2×a 2 ×t+3×a 3 ×t 2 +4×a 4 ×t 3 +5×a 5 ×t 4 ;

[0064] Ytˋˋ=2×a 2 +6×a 3 ×t+12×a 4 ×t 2 +20×a 5 ×t 3 ;

[0065] Where, Yt represents the longitudinal position; Ytˋ represents the longitudinal velocity; Ytˋˋ represents the longitudinal acceleration; a 0 、a 1 、a 2 、a 3 、a 4 and a 5 represents the 6 coefficients of the quintic polynomial, t represents time, a 0 Determines the longitudinal position of the vehicle at t = 0, a 1 Determines the speed of the vehicle at t = 0, a 2 Determines the initial acceleration, which ensures a smooth transition from the starting point to the expected driving state, a 3 Determines the terminal acceleration, a 4 Determines the termination speed, a 5 Determines the end point.

[0066] In some embodiments, optionally, the step of screening multiple second speed curves to obtain a third speed curve includes: screening multiple second speed curves according to preset constraints and cost values ​​to obtain a third speed curve; wherein the preset constraints include centripetal acceleration, longitudinal displacement of the mine car, coordinate point information, monotonicity of speed in acceleration and deceleration stages, maximum speed and maximum acceleration limits.

[0067] In this embodiment, multiple second speed curves can be screened according to preset constraints and cost values ​​to obtain a third speed curve. For example, the second speed curve satisfies the centripetal acceleration constraint, while ensuring that the longitudinal displacement is monotonically increasing, the planned end point coordinates do not exceed the target point coordinates, the speed is monotonous in the acceleration and deceleration stages, and the maximum speed and maximum acceleration limits.

[0068] In some embodiments, optionally, the step of determining the second target speed according to the third speed curve and the current GPS speed of the mine car includes: determining the second target speed using a first-order Bezier curve according to the third speed curve and the current GPS speed of the mine car.

[0069] In this embodiment, the first-order Bezier curve can be used to smooth the output speed according to the third speed curve and the current GPS speed of the mining vehicle to determine the target speed and avoid starting or braking too quickly.

[0070] In some embodiments, optionally, the target speed may be determined using the following formula:

[0071] K=min(spd_d,spd_a) / max(spd_d,spd_a);

[0072] Vfinal=K×spd_d+(1-K)×spd_a;

[0073] Wherein, K represents the coefficient of the first-order Bezier curve; Spd_d represents the expected speed of the current cycle; Spd_a represents the actual speed of the current cycle; Vfinal represents the final speed (target speed) calculated in the current cycle.

[0074] In some embodiments, optionally, after the step of controlling the travel of the mine car according to the first target speed or the second target speed, the travel control method of the autonomous driving mine car further includes: adjusting the following distance according to the current speed of the mine car, the braking response distance and the slope information.

[0075] In this embodiment, in the following mode, the current speed, brake response distance and slope information can be comprehensively considered to dynamically adjust the following distance, reduce speed fluctuations caused by behavioral decisions, and ensure safety.

[0076] In one embodiment according to the first aspect of the present application, Figure 2 As shown, a driving control method for an automatic driving mine car is provided, comprising:

[0077] S202, updating the speed curve at the current moment in real time according to the current vehicle posture information and the trajectory information output by the global planning.

[0078] S204, calculating the current acceleration value in real time, and performing conjugate gradient smoothing on the output global planning velocity information.

[0079] S206, based on the positions, speeds and accelerations of the starting and ending points where the speed needs to be planned, combined with the centripetal acceleration constraint at the turn, the monotonicity of the planned displacement, the monotonicity of the speed, the maximum speed, acceleration and jerk constraints, a quintic polynomial speed curve is planned, and the optimal curve is sorted and selected.

[0080] S208, based on the calculated speed value and the actual speed value, the speed is smoothed in combination with the first-order Bezier curve, and a trajectory including the position, speed, and timestamp is output to the control layer.

[0081] The driving control method of an autonomous driving mine car for an open-pit mine environment provided in the present application smoothes the globally planned speed through the conjugate gradient method at the front end, performs quintic polynomial planning based on the position, speed, and acceleration information of the starting point and the end point combined with the minimum acceleration and the minimum jerk (the derivative of the minimum acceleration) in the planning optimization, and performs first-order Bessel smoothing in combination with the output speed and the actual vehicle speed in the back-end optimization, and outputs the final expected speed to optimize transportation efficiency and improve driving comfort.

[0082] In one embodiment according to the first aspect of the present application, a driving control method for an autonomous driving mine car is provided, comprising a front-end optimization step, a planning optimization step, a back-end optimization step, and an output control instruction step. In the front-end optimization step, a conjugate gradient method is used to smooth the expected speed of the global planning.

[0083] In some embodiments, optionally, the driving control method of the autonomous mining vehicle further includes generating a plurality of speed curves according to a quintic polynomial, and screening and outputting the optimal curve based on constraint conditions.

[0084] In some embodiments, optionally, the back-end optimization step includes smoothing the output speed using a first-order Bezier curve and dynamically adjusting the following distance.

[0085] In some embodiments, optionally, the t value of the first-order Bezier curve is t=min(spd_d, spd_a) / max(spd_d, spd_a), wherein spd_d is the expected speed output by the quintic polynomial curve, and spd_a is the actual speed.

[0086] In some embodiments, optionally, the dynamically adjusted following distance includes factors such as current vehicle speed information, slope information, and response time of the brake actuator.

[0087] The following is a detailed introduction to the front-end optimization steps, planning optimization steps, back-end optimization steps, and output control instruction steps:

[0088] 1. Front-end optimization steps:

[0089] Expected speed smoothing: The expected speed of the global planning based on the high-precision map is segmented according to the terrain, and there are speed mutations. Therefore, the conjugate gradient method is used to smooth the expected speed of the global planning to reduce the speed mutations between adjacent planning frames and improve driving smoothness. The conjugate gradient method has the characteristics of high efficiency and fast convergence speed, and can quickly perform preliminary smoothing and optimization on the received speed information. The smoothing formula is as follows:

[0090] V i =V i ˋ-α×(V i ˋ-V i );

[0091] V i =V i ˋ-β×[(V i ˋ-V i-1 ˋ)+(V i ˋ-V i+1 ˋ)];

[0092] V i =V i ˋ-β×[(2×V i ˋ-V i-1 ˋ-V i+1 ˋ)];

[0093] Among them, V i ˋ represents the true value of the current element; V i Represents the fitting value of the current element; V i-1 ˋ represents the fitted value of the previous element of the current element; V i+1 ˋ represents the fitting value of the next element after the current element; α represents the fitting weight coefficient between the fitting value and the target value; β represents the smoothing weight coefficient of the difference between the current element and the previous element, and the difference between the current element and the next element.

[0094] 2. Planning optimization steps:

[0095] After smoothing the expected speed of the global plan, when the vehicle behavior changes, such as slowing down to stop, accelerating to overtake, starting after stopping, changing lanes, etc., the speed needs to change, and the original speed cannot meet the behavior change requirements. For this reason, planning optimization is required to generate speed planning information by combining the position, speed, and acceleration information of the starting and target points.

[0096] Real-time acceleration calculation: Integrate the vehicle's current position, speed, acceleration information, and the corresponding parameters of the end point, and use quintic polynomial interpolation to generate a speed curve to ensure the authenticity and continuity of the acceleration. The quintic polynomial interpolation formula is:

[0097] Yt=a 0 +a1 ×t+a 2 ×t 2 +a 3 ×t 3 +a 4 ×t 4 +a 5 ×t 5 ;

[0098] Ytˋ=a 1 +2×a 2 ×t+3×a 3 ×t 2 +4×a 4 ×t 3 +5×a 5 ×t 4 ;

[0099] Ytˋˋ=2×a 2 +6×a 3 ×t+12×a 4 ×t 2 +20×a 5 ×t 3 ;

[0100] Where, Yt represents the longitudinal position; Ytˋ represents the longitudinal velocity; Ytˋˋ represents the longitudinal acceleration; a 0 、a 1 、a 2 、a 3 、a 4 and a 5 Represents the 6 coefficients of the quintic polynomial, a 0 Determines the longitudinal position of the vehicle at t = 0, a 1 Determines the speed of the vehicle at t = 0, a 2 Determines the initial acceleration, which ensures a smooth transition from the starting point to the expected driving state, a 3 Determines the terminal acceleration, a 4 Determines the termination speed, a 5 Determines the end point.

[0101] Multi-curve generation and screening: In each planning cycle (the program is executed according to a timer and in a fixed cycle. When planning is required, the planning function is called in this cycle), multiple speed curves are generated based on the time sampling points, and are optimized based on the constraints (such as minimum acceleration, minimum jerk) and cost values ​​to output the optimal speed plan.

[0102] Planning includes three parts: sampling, searching, and optimization. Multiple sets of reference data will be generated according to the sampling situation, but in the end only one optimal result is needed as the output data, so a selection is required. The cost value is the basis for selecting the sampling result, and the data with the smallest cost value is selected as the output.

[0103] Constraint satisfaction: Ensure that the plan satisfies the centripetal acceleration constraint a=v 2 / r (a represents the centripetal acceleration, v represents the tangential speed when turning, and r represents the turning radius), while ensuring that the longitudinal displacement increases monotonically, the planned end point coordinates do not exceed the target point coordinates, the speed is monotonic in the acceleration and deceleration stages, and the maximum speed and maximum acceleration limits.

[0104] 3. Backend optimization steps:

[0105] Output speed smoothing: Combine the real-time calculated speed with the current GPS speed and use the first-order Bezier curve to smooth the output speed to avoid starting or braking too quickly. Specifically, the following formula can be used to smooth the output speed:

[0106] K=min(spd_d,spd_a) / max(spd_d,spd_a);

[0107] Vfinal=K×spd_d+(1-K)×spd_a;

[0108] Wherein, K represents the coefficient of the first-order Bezier curve; Spd_d represents the expected speed of the current cycle; Spd_a represents the actual speed of the current cycle; Vfinal represents the final speed calculated in the current cycle.

[0109] Dynamic following distance adjustment: In following mode, the system dynamically adjusts the following distance by comprehensively considering the current speed, brake response distance and slope information to reduce speed fluctuations caused by behavioral decisions and ensure safety.

[0110] 4. Output control instruction steps:

[0111] The output includes posture information, expected speed, timestamp, etc., which are used by the control module to perform precise position control and closed-loop feedback to improve driving stability and accuracy.

[0112] This application solves key issues such as smoothness, computational efficiency, comfort and safety in speed planning of open-pit mine autonomous driving, provides advanced and reliable technical support for mine automated transportation, and achieves the following beneficial effects:

[0113] 1. Significantly improve the comfort and safety of autonomous vehicles in open-pit mine operations, and effectively avoid safety hazards such as emergency stop failures caused by improper speed planning.

[0114] 2. Reduce frequent emergency braking, reduce the risk of thermal decay of the brake system, and extend the life of the brake actuator.

[0115] 3. Avoid vehicle stalling caused by abnormal gearbox gear position and ensure the continuity and reliability of transportation operations.

[0116] 4. Improve overall transportation efficiency and reduce operating costs through refined speed control.

[0117] like Figure 3 As shown, an embodiment of the second aspect of the present invention provides a driving control device 1 for an automatic driving mine car, comprising: an acquisition module 11, used to acquire a speed curve in the global path planning of the mine car; a first processing module 12, used to smooth the speed curve to obtain a first speed curve; a first determination module 13, used to determine whether the mine car has a target behavior; a first control module 14, used to determine a first target speed according to the first speed curve and the current GPS speed of the mine car when it is determined that the mine car has not had the target behavior, and control the mine car to travel according to the first target speed; a second determination module 15, used to acquire the current position information, speed information, acceleration information and parameter information of the end point of the mine car when it is determined that the mine car has had the target behavior; a second processing module 16, used to generate a plurality of second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point; a screening module 17, used to screen the plurality of second speed curves to obtain a third speed curve; a third determination module 18, used to determine a second target speed according to the third speed curve and the current GPS speed of the mine car; a second control module 19, used to control the mine car to travel according to the second target speed.

[0118] The driving control device 1 of the automatic driving mine car provided by the present invention comprises an acquisition module 11, a first processing module 12, a first control module 14, a first determination module 13, a second control module 19, a second determination module 15, a second processing module 16, a screening module 17 and a third determination module 18. The acquisition module 11 can acquire the speed curve in the global path planning of the mine car. The first processing module 12 can smooth the speed curve to obtain the first speed curve. The first determination module 13 can determine whether the mine car has a target behavior. The first control module 14 can determine the first target speed according to the first speed curve and the current GPS speed of the mine car when it is determined that the mine car has not had a target behavior, and control the mine car to travel according to the first target speed. The second determination module 15 can acquire the current position information, speed information, acceleration information and parameter information of the end point of the mine car when it is determined that the mine car has a target behavior. The second processing module 16 can generate multiple second speed curves according to the current position information, speed information, acceleration information and parameter information of the end point. The screening module 17 can screen multiple second speed curves to obtain a third speed curve. The third determination module 18 can determine the second target speed according to the third speed curve and the current GPS speed of the mine car. The second control module 19 can control the mine car to travel according to the second target speed. The driving control device 1 of the automatic driving mine car provided by the present invention can reduce the sudden change of speed by smoothing the speed curve in the global path planning of the mine car, thereby improving the comfort and stability of the vehicle. The second speed curve is generated according to the current position information, speed information, acceleration information and parameter information of the end point of the mine car, which can ensure that the speed curve remains continuous and smooth during the change process. The first target speed is determined according to the first speed curve and the current GPS speed of the mine car, or the second target speed is determined according to the third speed curve and the current GPS speed of the mine car, which is to merge the planned speed curve with the actual vehicle speed to ensure that the vehicle is more stable when performing actions and that the vehicle will not be too sudden when starting or stopping.

[0119] like Figure 4 As shown, an embodiment of the third aspect of the present invention provides a driving control device 2 for an autonomous mining car, comprising: a memory 22 and a processor 24, wherein the memory 22 stores programs or instructions, and when the programs or instructions are executed by the processor 24, the steps of the driving control method for an autonomous mining car as in any one of the embodiments of the first aspect are implemented.

[0120] The driving control device 2 of the autonomous mine car provided by the present invention comprises a memory 22 and a processor 24, wherein the memory 22 stores a program or instruction, and when the program or instruction is executed by the processor 24, the steps of the driving control method of the autonomous mine car in any one of the embodiments of the first aspect are implemented. Since the driving control device of the autonomous mine car can implement the steps of the driving control method of the autonomous mine car in any one of the embodiments of the first aspect. Therefore, the driving control device 2 of the autonomous mine car provided by the present invention also has all the beneficial effects of the driving control method of the autonomous mine car in any one of the embodiments of the first aspect, which will not be repeated here.

[0121] An embodiment of the fourth aspect of the present invention provides a readable storage medium having a program or instruction stored thereon. When the program or instruction is executed, the steps of the driving control method of the autonomous driving mining car in any one of the embodiments of the first aspect are implemented.

[0122] According to the readable storage medium provided by the present invention, a program or instruction is stored thereon, and when the program or instruction is executed, the steps of the driving control method of the autonomous driving mine car in any embodiment of the first aspect are implemented. Since the readable storage medium can implement the steps of the driving control method of the autonomous driving mine car in any embodiment of the first aspect. Therefore, the readable storage medium provided by the present invention also has all the beneficial effects of the driving control method of the autonomous driving mine car in any embodiment of the first aspect, which will not be repeated here.

[0123] It should be noted that, in this article, the terms "comprise", "include" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or device including a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the sentence "comprise one..." do not exclude the presence of other identical elements in the process, method, article or device including the element. In addition, it should be pointed out that the scope of the methods and devices in the embodiments of the present application is not limited to performing functions in the order shown or discussed, and may also include performing functions in a substantially simultaneous manner or in reverse order according to the functions involved, for example, the described method may be performed in an order different from that described, and various steps may also be added, omitted, or combined. In addition, the features described with reference to certain examples may be combined in other examples.

[0124] Through the description of the above implementation methods, those skilled in the art can clearly understand that the above-mentioned embodiment methods can be implemented by means of software plus a necessary general hardware platform, and of course by hardware, but in many cases the former is a better implementation method. Based on such an understanding, the technical solution of the present application, or the part that contributes to the prior art, can be embodied in the form of a computer software product, which is stored in a storage medium (such as ROM / RAM, a disk, or an optical disk), and includes a number of instructions for a terminal (which can be a mobile phone, a computer, a server, or a network device, etc.) to execute the methods described in each embodiment of the present application.

[0125] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0126] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A driving control method for an automatic driving mine car, characterized in that: include: Get the speed curve in the global path planning of the mine car; Smoothing the speed curve to obtain a first speed curve; Determining whether the minecart has a target behavior; When it is determined that the mine car does not have the target behavior, a first target speed is determined according to the first speed curve and the current GPS speed of the mine car, and the mine car is controlled to travel according to the first target speed; When it is determined that the mine car has the target behavior, obtaining current position information, speed information, acceleration information and parameter information of the end point of the mine car; generating a plurality of second speed curves according to the current position information, the speed information, the acceleration information and the parameter information of the end point; Screening a plurality of the second speed curves to obtain a third speed curve; Determining a second target speed according to the third speed curve and the current GPS speed of the mining vehicle; The mining vehicle is controlled to travel according to the second target speed.

2. The driving control method of the automatic driving mine car according to claim 1, characterized in that: The step of smoothing the speed curve to obtain a first speed curve comprises: The velocity curve is smoothed by using a conjugate gradient method to obtain a first velocity curve.

3. The driving control method of the automatic driving mine car according to claim 1, characterized in that: The target behaviors include: Cruising, slowing down to stop, accelerating to overtake, starting after stopping and changing lanes.

4. The driving control method of the automatic driving mine car according to claim 1, characterized in that: The step of generating a plurality of second speed curves according to the current position information, the speed information, the acceleration information and the parameter information of the end point comprises: A plurality of the second speed curves are generated by using quintic polynomial interpolation according to the current position information, the speed information, the acceleration information and the parameter information of the end point.

5. The driving control method of the automatic driving mine car according to claim 1, characterized in that: The step of screening the plurality of second speed curves to obtain a third speed curve comprises: Screening the plurality of second speed curves according to preset constraints and cost values ​​to obtain a third speed curve; The preset constraints include centripetal acceleration, longitudinal displacement of the mine car, coordinate point information, monotonicity of speed in acceleration and deceleration stages, maximum speed and maximum acceleration limits.

6. The driving control method of the automatic driving mine car according to claim 1, characterized in that: The step of determining the second target speed according to the third speed curve and the current GPS speed of the mining vehicle comprises: The second target speed is determined by using a first-order Bezier curve according to the third speed curve and the current GPS speed of the mining vehicle.

7. The driving control method of an automatic driving mining vehicle according to any one of claims 1 to 6, characterized in that: After the step of controlling the mine car to travel according to the first target speed or the second target speed, the driving control method of the automatic driving mine car further includes: The following distance is adjusted according to the current speed, brake response distance and slope information of the mine car.

8. A driving control device for an automatic driving mine car, characterized in that: include: The acquisition module is used to obtain the speed curve in the global path planning of the mine car; A first processing module, used for smoothing the speed curve to obtain a first speed curve; A first determination module, used to determine whether the mine car has a target behavior; a first control module, configured to determine a first target speed according to the first speed curve and a current GPS speed of the mine car when it is determined that the mine car has not performed the target behavior, and control the mine car to travel according to the first target speed; A second determination module is used to obtain current position information, speed information, acceleration information and end point parameter information of the mine car when it is determined that the mine car has the target behavior; A second processing module, configured to generate a plurality of second speed curves according to the current position information, the speed information, the acceleration information and the parameter information of the end point; A screening module, used for screening the plurality of second speed curves to obtain a third speed curve; A third determination module, used to determine a second target speed according to the third speed curve and the current GPS speed of the mining vehicle; The second control module is used to control the movement of the mining vehicle according to the second target speed.

9. A driving control device for an automatic driving mine car, characterized in that: include: A memory and a processor, wherein the memory stores a program or an instruction, and when the program or the instruction is executed by the processor, the steps of the driving control method of the autonomous driving mining vehicle as described in any one of claims 1 to 7 are implemented.

10. A readable storage medium, characterized in that: A program or instruction is stored thereon, and when the program or instruction is executed, the steps of the driving control method of the automatic driving mining vehicle as described in any one of claims 1 to 7 are implemented.

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